This is a very easy and fun to build project that will allow you to control up to eight external devices through your computer's parallel port. You may for instance control different appliances such as lamps, computers, printers, tv sets, radios, music systems, air conditioners, air fans, garden sprinklers and anything else you can think of, all through your computer.

Stepper motor driver that will allow you to precisely control a unipolar stepper motor through your computer's parallel port. With a stepper motor you can build a lot of interesting gadgets such as robots, elevator, PCB drilling mill, camera panning system, automatic fish feeder, etc. If you have never worked with stepper motors before you will surely have a lot of fun with this project.

High fidelity external USB Soundcard / USB Headphones project that can be built for your PC or Mac. It is based on the latest PCM2706 IC which functions as a high quality, crystal clear 16-BIT Stereo DAC. It is a single chip digital-to-analog converter that offers two D/A output stereo channels, digital S/PDIF output and requires very few external components. PCM2706 includes integrated USB 1.0 & USB 2.0 compliant interface controller and it is conveniently powered directly from USB connection. PCM2706 is a USB plug-and-play device and does not require any driver installation under Windows XP and Mac OSX.

With this project you can show the temperature on you PC. This thermometer plugs on any free serial port. It gives temperature readings accurate to 0.5°C with no calibration.The project consists of the AVR 2313 Project board and the DS1621 Thermometer board and software for the PC.

Each fan turns off when the temperature drops 5 degrees below its turn-on temperature. For example, if the dial is set to 80 degrees, the fan turns on at 80 degrees and turns off at 75 degrees. This prevents the fan from cycling on and off rapidly, which would occur if the fan turned on at 80, started to cool the cabinet, and then immediately turned off at 79.

PC LED Load is a device and software designed to display many shades of colors from green to red on your computer case LED. Colors are controlled completely by software and can be updated in real-time.
The PC LED Load circuit board is connected to one of the internal USB ports found on most newer motherboards. The only actual case modification required is in replacing the two (or more) front panel LEDs with tri-color versions. These are then connected to the PC LED Load circuit board.

This project's purpose is to design a fully automated machine for drilling a printed circuit board, (PCB) blank at a minimum cost and with the minimum amount of custom machining. This low cost philosophy is achieved by adapting the existing mechanical assemblies from readily available computer peripherals and electronic measuring instruments. Drill data is transferred to the PCDrill from an Excellon drill file generated by a PCB CAD program running on a personal computer.

A few time ago I decided to create a media center box to replace my DVD player, satellite receiver, VCR and my kid's Play Station 2, to one device. So, I made a core 2 duo processor system that actually replaced with succeed, all my electronic devices. The only thing that was missing was a remote control to switch On/Off my Media Center. After I searched on the net to buy a complete remote control system, I saw that the price was a little bit high (about 90 euros). I checked my stuff to find my old 7-in-one remote control that I had bought 2 years ago and I started to build my own remote control receiver circuit.

RS232 ports of modern laptops are not always complying with the original RS232 standard. If RS232 levels are expected to be +/- 12 volts, most of the time laptops RS232 ports produce in fact +/- 5 volts levels. For most peripherals, this is not an issue and they are responding as expected.

This article shows how to use the PIC16F84 microcontroller with PicBasic to design a quick & effective, serially controlled, I/O-Expander. Using PicBasic makes developing handy single-chip devices like this extremely simple.

Build your own Accurate LC Meter (Capacitance Inductance Meter) and start making your own coils and inductors. This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils and inductors. LC Meter can measure inductances starting from 10nH - 1000nH, 1uH - 1000uH, 1mH - 100mH and capacitances from 0.1pF up to 900nF. The circuit includes an auto ranging as well as reset switch and produces very accurate and stable readings.

Volt Ampere Meter measures voltage of 0-70V or 0-500V with 100mV resolution and current consumption 0-10A or more with 10mA resolution. The meter is a perfect addition to any power supply, battery chargers and other electronic projects where voltage and current must be monitored. The meter uses PIC16F876A microcontroller with 16x2 backlighted LCD.

Frequency Meter / Counter measures frequency from 10Hz to 60MHz with 10Hz resolution. It is a very useful bench test equipment for testing and finding out the frequency of various devices with unknown frequency such as oscillators, radio receivers, transmitters, function generators, crystals, etc.

ESR Meter kit is an amazing multimeter that measures ESR values, capacitance (100pF - 20,000uF), inductance, resistance (0.1 Ohm - 20 MOhm),
tests many different types of transistors such as NPN, PNP, FETs, MOSFETs, Thyristors, SCRs, Triacs and many types of diodes.
It also analyzes transistor's characteristics such as voltage and gain. It is an irreplaceable tool for troubleshooting and repairing electronic equipment by determining performance and health of electrolytic capacitors. Unlike other ESR Meters that only measure ESR value this one measures capacitor's ESR value as well as its capacitance all at the same time.

Arduino Prototype is a spectacular development board fully compatible with Arduino Pro. It's breadboard compatible so it can be plugged into a breadboard for quick prototyping, and it has VCC & GND power pins available on both sides of PCB. It's small, power efficient, yet customizable through onboard 2 x 7 perfboard that can be used for connecting various sensors and connectors. Arduino Prototype uses all standard through-hole components for easy construction, two of which are hidden underneath IC socket. Board features 28-PIN DIP IC socket, user replaceable ATmega328 microcontroller flashed with Arduino bootloader, 16MHz crystal resonator and a reset switch. It has 14 digital input/output pins (0-13) of which 6 can be used as PWM outputs and 6 analog inputs (A0-A5). Arduino sketches are uploaded through any USB-Serial adapter connected to 6-PIN ICSP female header. Board is supplied by 2-5V voltage and may be powered by a battery such as Lithium Ion cell, two AA cells, external power supply or USB power adapter.

Having the ability to control various appliances inside or outside of your house wirelessly is a huge convenience, and can make your life much easier and fun. RF remote control provides long range of up to 200m / 650ft and can find many uses for controlling different devices, and it works even through the walls. You can control lights, fans, AC system, computer, printer, amplifier, robots, garage door, security systems, motor-driven curtains, motorized window blinds, door locks, sprinklers, motorized projection screens and anything else you can think of.